Mechanical door locks for locking and unlocking a door with a metal key have mainly been used as door locking devices in an office, hotel, apartment, etc. However, the conventional mechanical door locks are poor in security because the metal key as a door locking and unlocking means is vulnerable to inadvertent loss and unwanted duplication. At present, in consideration of the vulnerability of the conventional mechanical door lock, use is made of a variety of door locks such as a door lock for locking and unlocking the door with a magnet card type or smart card type electronic key, a door lock for locking and unlocking the door by a key input of a secret number and so on. Moreover, active research and commercialization is conducted for door locks capable of locking and unlocking the door through a bio recognition of the inherent characteristic of a specified part of a human body such as a voice recognition, fingerprint recognition, face recognition, etc.
In the meantime, information communication technologies represented by the Internet and mobile communications have been changing the living patterns of the moderns. Specifically, Internet-feasible personal computers have been spread into almost all of the homes, schools and offices, allowing the user to acquire information using web sites, purchase goods through electronic transactions and exchange news through E-mails. Additionally, through the use of a mobile communication terminal, it has become to provide diversified services such as financial settlement, home automation, use of wireless Internet, etc., in addition to the voice call-oriented mobile communication service.
At an initial stage, the information communication technologies were separately developed depending on their purposes of use such as computers, mobile communications, broadcastings and the like. Nowadays, the technologies have a tendency to be developed in convergence. A representative example of the convergence of the information communication technologies may be a home network. Home electronic appliances begin to emerge that can interact with the Internet and/or mobile communications to thereby construct a home network. In other words, it was conventionally possible for a user to directly manipulate a TV receiver, a washing machine, etc. only inside the house, but at present, the user can control, even outside the house, various kinds of home electronic appliances such as a TV receiver, a washing machine, a lighting equipment and an oven through the use of a mobile communication terminal connected to the Internet.
Meanwhile, the conventional door locks are generally of a stand-alone type that can perform only the functions set by the hardware and software preliminarily equipped at their manufacturing process. This makes it impossible to expand the functions of the door lock unless the door lock itself is replaced as a whole, even if the user wishes to enjoy additional functions such as crime prevention, fire detection and home network.